Sputtering apparatus including gas distribution system

ABSTRACT

Some embodiments provide a magnetron sputtering apparatus including a vacuum chamber within which a controlled environment may be established, a target comprising one or more sputterable materials, wherein the target includes a racetrack-shaped sputtering zone that extends longitudinally along a longitudinal axis and comprises a straightaway area sandwiched between a first turnaround area and a second turnaround area, a gas distribution system that supplies a first gas mixture to the first turnaround area and/or the second turnaround area and supplies a second gas mixture to the straightaway area, wherein the first gas mixture reduces a sputtering rate relative to the second gas mixture. In some cases, the first gas mixture includes inert gas having a first atomic weight and the second gas mixture includes inert gas having a second atomic weight, wherein the second atomic weight is heavier than the first atomic weight.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of and claims priority to U.S.patent application Ser. No. 16/184,447, filed on Nov. 8, 2018, which isa continuation of U.S. patent application Ser. No. 15/725,456, filed onOct. 5, 2017 and which is now abandoned, which is a continuation of U.S.patent application Ser. No. 15/013,120, filed on Feb. 2, 2016 and issuedas U.S. Pat. No. 9,812,296, which claims priority to U.S. ProvisionalPatent Application Ser. No. 62/111,318, filed on Feb. 3, 2015, each ofwhich is hereby incorporated by reference into this application.

FIELD OF THE INVENTION

The invention relates to apparatuses, systems and methods for sputteringthin films onto surfaces. More particularly, the invention relates tosputtering apparatuses, systems and methods that use a gas distributionsystem that improves uniformity in sputtered thin film thicknesses.

BACKGROUND OF THE INVENTION

In many industries, it is desirable to deposit films onto surfaces of asubstrate to provide desired characteristics to the finished coatedproduct. For example, in the glass industry, it is often desirable todeposit films to provide characteristics to the glass related totransmittance, emissivity, reflectivity, durability, color,photocatalysis and chemical resistance.

One deposition method used to deposit films onto substrates is asputtering method. During sputtering, a substrate is positioned within avacuum chamber containing a rotating cylindrical target or planar targetthat has sputterable target material on its outer surface. An electricalfield is created between the target (which acts as a cathode) and ananode in the vacuum chamber. Next, an argon gas is introduced to thevacuum chamber. Electrons in the electrical field ionize the gas atomsand create charged plasma. Sputtering occurs when plasma particlesimpinge on the surface of the target causing emission of sputterabletarget material onto a substrate.

Certain sputtering systems include magnets that create a magnetic field.Sputtering systems including magnets are often referred to as magnetronsputtering systems. The magnetic field confines the plasma within arelatively narrowly defined area along a target surface. Typically,magnets are placed behind or within the target and are arranged so thatthe plasma is confined at the bottom surface of the planar orcylindrical target, facing a substrate being coated directly beneath.The plasma sputters target material from this bottom surface, therebyforming a sputtering zone on the target.

In many cases, the magnets are arranged such that a sputtering zone isformed on the target surface. A problem with many previous sputteringsystems is that plasma confined at certain areas tends to be denser thanplasma confined at other areas. The denser the plasma, the higher thesputtering rate is of target material confined by the plasma. Thus,certain areas have denser plasma than other areas, the target materialis sputtered at different rates. As a result, the target is sputtered inan uneven fashion such that the deposited film is non-uniform.

It would be desirable to provide sputtering apparatuses, systems andmethods that sputter target material to deposit films having a moreuniform thickness. It would also be desirable to provide sputteringapparatuses, systems and methods that provide a more uniform sputteringrate along the entire sputtering zone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing depicting a magnetron sputtering systemincluding a gas distribution system in accordance with an embodiment,wherein the gas distribution system includes two gas delivery memberspositioned on each side of a sputtering target and connected to a singlegas source.

FIG. 2 is a schematic drawing depicting a magnetron sputtering systemincluding a gas distribution system in accordance with anotherembodiment, wherein the gas distribution system includes two gasdelivery members positioned on each side of a sputtering target and eachconnected to two separate gas sources.

FIG. 3 is a schematic drawing depicting a magnetron sputtering systemincluding a gas distribution system in accordance with anotherembodiment, wherein the gas distribution system includes a single gasdelivery member positioned to substantially entirely surround asputtering target and connected to a single gas source.

FIG. 4 is a schematic drawing depicting a magnetron sputtering systemincluding a gas distribution system in accordance with anotherembodiment, wherein the gas distribution system includes a single gasdelivery member positioned to substantially entirely surround asputtering target and connected to two separate gas sources.

FIG. 5 is a schematic drawing depicting a magnetron sputtering systemincluding a gas distribution system in accordance with anotherembodiment, wherein the gas distribution system includes two gasdelivery members positioned on each side of a sputtering target and topartially surround ends of the sputtering target and connected to asingle gas source.

FIG. 6 is a schematic drawing depicting a magnetron sputtering systemincluding a gas distribution system in accordance with anotherembodiment, wherein the gas distribution system includes two gasdelivery members positioned on each side of a sputtering target and topartially surround ends of the sputtering target and connected to twoseparate gas sources.

FIG. 7 is a bottom view of a sputtering target having a generalsputtering zone in accordance with an embodiment.

FIG. 8 is a bottom view of a sputtering target having a racetrack-shapedsputtering zone in accordance with an embodiment.

FIG. 9 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply two gas mixtures from a single gas source and arearranged along each side of a sputtering target.

FIG. 10 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply two gas mixtures from a single gas source and arearranged to substantially entirely surround a sputtering target.

FIG. 11 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply two gas mixtures from a single gas source and arearranged along each side of a sputtering target and to partiallysurround ends of the sputtering target.

FIG. 12 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply two gas mixtures from two gas sources and arearranged along each side of a sputtering target.

FIG. 13 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply two gas mixtures from two gas sources and arearranged to substantially entirely surround a sputtering target.

FIG. 14 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply two gas mixtures from two gas sources and arearranged along each side of a sputtering target and to partiallysurround ends of the sputtering target.

FIG. 15 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply three gas mixtures from a single gas source andare arranged along each side of a sputtering target.

FIG. 16 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply three gas mixtures from a single gas source andare arranged to substantially entirely surround a sputtering target.

FIG. 17 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply three gas mixtures from a single gas source andare arranged along each side of a sputtering target and to partiallysurround ends of the sputtering target.

FIG. 18 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply three gas mixtures from two gas sources and arearranged along each side of a sputtering target.

FIG. 19 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply three gas mixtures from two gas sources and arearranged to substantially entirely surround a sputtering target.

FIG. 20 is a schematic drawing depicting an arrangement of interfaces ofa gas distribution system in accordance with another embodiment, whereinthe interfaces supply three gas mixtures from two gas sources and arearranged along each side of a sputtering target and to partiallysurround ends of the sputtering target.

FIG. 21 is bottom view of a sputtering target and two gas distributionmembers of a gas distribution system in accordance with an embodiment,wherein each gas distribution member is positioned along each side of asputtering target.

FIG. 22 is bottom view of a sputtering target and a single gasdistribution member of a gas distribution system in accordance with anembodiment, wherein the single gas distribution member is positioned tosubstantially entirely surround the sputtering target.

FIG. 23 is bottom view of a sputtering target and two gas distributionmembers of a gas distribution system in accordance with an embodiment,wherein each gas distribution member is positioned along each side of asputtering target and to partially surround ends of the sputteringtarget.

FIG. 24 is bottom view of a sputtering target and a plurality of gasdistribution members of an anodic gas distribution system in accordancewith an embodiment, wherein the gas distribution members are positionedalong each side of a sputtering target and certain gas distributionmembers are anodic gas distribution members.

FIG. 25 is bottom view of a sputtering target and a plurality of gasdistribution members of an anodic gas distribution system in accordancewith an embodiment, wherein the gas distribution members are positionedto substantially entirely surround the sputtering target and certain gasdistribution members are anodic gas distribution members.

FIG. 26 is bottom view of a sputtering target and a plurality of gasdistribution members of an anodic gas distribution system in accordancewith an embodiment, wherein the gas distribution members are positionedto substantially entirely surround the sputtering target and certain gasdistribution members are anodic gas distribution members.

FIG. 27 is bottom view of a sputtering target and a plurality gasdistribution members of an anodic gas distribution system in accordancewith an embodiment, wherein the gas distribution members are positionedalong each side of the sputtering target and to partially surround endsof the sputtering target and certain gas distribution members are anodicgas distribution members.

SUMMARY

Certain embodiments provide a magnetron sputtering apparatus thatincludes a vacuum chamber within which a controlled environment may beestablished, a target including one or more sputterable materials,wherein the target includes a sputtering zone that extendslongitudinally along a longitudinal axis, and a gas distribution systemcomprising a plurality of interfaces extending along the longitudinalaxis, wherein the plurality of interfaces includes a first interface anda second interface. A first gas mixture is supplied to the firstinterface and a second gas mixture is supplied to the second interface,wherein the first gas supply supplies a first gas mixture and the secondgas supply supplies a second gas mixture, wherein the first gas mixtureincludes inert gas having a first atomic weight and the second gasmixture includes inert gas having a second atomic weight, wherein thefirst atomic weight is different from the second atomic weight. In somecases, the second atomic weight is heavier than the first atomic weight.

In some cases, the first gas mixture can include a single inert gasselected from the group consisting of argon, helium neon, krypton, xenonand radon and the first atomic weight is an atomic weight of the singleinert gas and/or the second gas mixture can include a single inert gasselected from the group consisting of argon, helium neon, krypton, xenonand radon and the second atomic weight is an atomic weight of the singleinert gas. In other cases, the first gas mixture can include an inertgas mixture including (or consisting essentially of) two or more inertgases selected from the group consisting of argon, helium neon, krypton,xenon and radon and the first atomic weight is an average atomic weightof the two or more inert gases and/or the second gas mixture can includean inert gas mixture including (or consisting essentially of) two ormore inert gases selected from the group consisting of argon, heliumneon, krypton, xenon and radon and the second atomic weight is anaverage atomic weight of the two or more inert gases.

Also, in some cases, at least one interface in the plurality ofinterfaces supplies gas at a continuous flow rate and/or at a continuouspressure. In other cases, at least one interface in the plurality ofinterfaces supplies gas at a non-continuous flow rate and/or at anon-continuous pressure. Also, the first gas mixture and the second gasmixture can be substantially free of reactive gas. Further, in somecases, the first gas mixture is supplied to the first interface at afirst gas pressure and the second gas mixture is supplied to the secondinterface at a second gas pressure, wherein the first gas pressure issubstantially the same as the second gas pressure.

In some embodiments, the gas distribution system includes a first gasdistribution member that houses the first interface and a second gasdistribution member that houses the second interface. In some cases, thefirst gas distribution system is an anodic gas distribution member andthe second gas distribution system is a non-anodic gas distributionmember, wherein the anodic gas distribution member receives a voltage.In other cases, the first gas distribution member is a first anodic gasdistribution member and the second gas distribution member is a secondanodic gas distribution member, wherein the first anodic gasdistribution member is insulated from the second anodic gas distributionmember, and wherein the first anodic gas distribution member receives afirst voltage and the second gas distribution member receives a secondvoltage, wherein the first voltage and the second voltage are different.

In certain embodiments, the sputtering zone is a racetrack-shapedsputtering zone comprising a straightaway area sandwiched between afirst turnaround area and a second turnaround area, wherein the firstinterface positions along the first turnaround area or the secondturnaround area and the second interface positions along thestraightaway area. In some cases, the first interface comprises aplurality of first interfaces that substantially surround at least aportion of the first turnaround area or the second turnaround area. Incertain cases, the plurality of first interfaces substantially entirelysurrounds the first turnaround area or the second turnaround area. Insuch cases, the gas distribution system can include an anodic gasdistribution member that houses the first interface and receives avoltage that reduces a sputtering rate of the first turnaround area orthe second turnaround area relative to a sputtering rate of thestraightaway area.

In some embodiments, the plurality of interfaces further includes athird interface and a third gas mixture is supplied to the thirdinterface and the third gas mixture includes inert gas having a thirdatomic weight, wherein the third atomic weight is different from eachthe first atomic weight and the second atomic weight. In some cases, thesecond atomic weight is heavier than the first atomic weight and thethird atomic weight is heavier than the first atomic weight but lighterthan the second atomic weight. Also, in some cases, the third gasinterface is sandwiched between the first interface and the secondinterface. The third gas mixture can also include a single inert gasselected from the group consisting of argon, helium neon, krypton, xenonand radon and the third atomic weight is an atomic weight of the singleinert gas or the third gas mixture includes two or more inert gasesselected from the group consisting of argon, helium neon, krypton, xenonand radon and the third atomic weight is an average atomic weight of thetwo or more inert gases. Further, in some cases, the first gas mixtureis supplied to the first interface at a first gas pressure, the secondgas mixture is supplied to the second interface at a second gas pressureand the third gas mixture is supplied to the third interface at a thirdgas pressure, wherein the first gas pressure, the second gas pressureand the third gas pressure are substantially the same.

In other embodiments, a magnetron sputtering apparatus is provided thatincludes a vacuum chamber within which a controlled environment may beestablished, a target comprising one or more sputterable materials,wherein the target includes a sputtering zone that extendslongitudinally along a longitudinal axis, and a gas distribution systemcomprising a plurality gas distribution members, wherein the pluralityof gas distribution members includes a first anodic gas distributionmember and a second anodic gas distribution member, wherein the firstanodic gas distribution member is insulated from the second anodic gasdistribution member, and wherein the first anodic gas distributionremember receives a first voltage and the second anodic gas distributionmember receives a second voltage, wherein the first voltage is differentthan the second voltage. In some cases, the first voltage and/or thesecond voltage is an adjustable voltage. Also, in some cases, the firstvoltage and/or the second voltage is a pulsed voltage.

In some embodiments, the sputtering zone is a racetrack-shapedsputtering zone comprising a straightaway area sandwiched between afirst turnaround area and a second turnaround area, wherein the firstanodic gas distribution member supplies gas to either the firstturnaround area or the second turnaround area and the second anodic gasdistribution member supplies gas to the straightaway area, wherein thefirst voltage is lower than the second voltage. In some cases, the firstanodic gas distribution member includes a plurality of interfaces thatsubstantially surround at least a portion of the first turnaround areaor the second turnaround area. In other cases, the first anodic gasdistribution member includes a plurality of interfaces thatsubstantially surround an entire first turnaround area or the secondturnaround area.

Also, in some embodiments, the first anodic gas distribution membersupplies a first gas mixture and the second anodic gas distributionmember supplies a second gas mixture, wherein the first gas mixtureincludes an inert gas having a first atomic weight and a second gasmixture including inert gas having a second atomic weight, wherein thefirst atomic weight is different from the second atomic weight. In somecases, the second atomic weight is heavier than the first atomic weight.

Other embodiments provide a magnetron sputtering apparatus including avacuum chamber within which a controlled environment may be established,a target comprising one or more sputterable materials, wherein thetarget includes a racetrack-shaped sputtering zone that extendslongitudinally along a longitudinal axis and comprises a straightawayarea sandwiched between a first turnaround area and a second turnaroundarea, and a gas distribution system comprising a plurality gasdistribution members, wherein the plurality of gas distribution membersincludes an anodic gas distribution member and a non-anodic gasdistribution member, wherein the anodic gas distribution member isinsulated from the non-anodic gas distribution member, and wherein theanodic gas distribution member supplies gas to either the firstturnaround area or the second turnaround area and receives a voltagethat reduces a sputtering rate of the first turnaround area or thesecond turnaround area relative to the straightaway area. In some cases,the first voltage and/or the second voltage is an adjustable voltage.Also, in some cases, the first voltage and/or the second voltage is apulsed voltage.

In some embodiments, the anodic gas distribution member includes aplurality of interfaces that substantially surround at least a portionof the first turnaround area or the second turnaround area. In somecases, the anodic gas distribution member includes a plurality ofinterfaces that substantially surround an entire first turnaround areaor the second turnaround area. In some cases, the anodic gasdistribution member supplies a first gas mixture and the non-anodic gasdistribution member supplies a second gas mixture, wherein the first gasmixture includes an inert gas having a first atomic weight and a secondgas mixture including inert gas having a second atomic weight, whereinthe first atomic weight is different from the second atomic weight. Insome cases, the second atomic weight is heavier than the first atomicweight.

Other embodiments provide a magnetron sputtering apparatus including avacuum chamber within which a controlled environment may be established,a target comprising one or more sputterable materials, wherein thetarget includes a racetrack-shaped sputtering zone that extendslongitudinally along a longitudinal axis and comprises a straightawayarea sandwiched between a first turnaround area and a second turnaroundarea, a gas distribution system that supplies a first gas mixture to thefirst turnaround area and/or the second turnaround area and supplies asecond gas mixture to the straightaway area, wherein the first gasmixture reduces a sputtering rate relative to the second gas mixture. Insome cases, the first gas mixture includes inert gas having a firstatomic weight and the second gas mixture includes inert gas having asecond atomic weight, wherein the second atomic weight is heavier thanthe first atomic weight.

DETAILED DESCRIPTION

The following detailed description is to be read with reference to thedrawings, in which like elements in different drawings have likereference numerals. The drawings, which are not necessarily to scale,depict selected embodiments and are not intended to limit the scope ofthe invention. Skilled artisans will recognize that the examplesprovided herein have many useful alternatives that fall within the scopeof the invention.

The present invention relates to a new gas distribution system thathelps provide a more uniform sputtering rate along a sputtering zone ona target. The gas distribution system is part of a magnetron sputteringsystem. FIGS. 1-7 each depict a standard magnetron sputtering system 10having different embodiments of the new gas distribution system.Generally, the sputtering system 10 includes a vacuum chamber 12defining a controlled environment, a cathode assembly 14 including atarget 16 having one or more sputterable target materials, and the gasdistribution system 18.

Sputtering techniques and equipment utilized in magnetron sputteringsystems are quite well known in the present art. For example, magnetronsputtering chambers and related equipment are available commerciallyfrom a variety of sources (e.g., Grenzebach or Soleras). Examples ofuseful magnetron sputtering techniques and equipment are also disclosedin U.S. Pat. No. 4,166,018, issued to Chapin, the entire teachings ofwhich are incorporated herein by reference.

The vacuum chamber 12 generally includes metallic walls, typically madeof steel or stainless steel, operably assembled to form a chamber thatcan accommodate a vacuum in which the sputtering process may occur. Avacuum source 20 is operably connected to the vacuum chamber 12 toprovide a controlled vacuum environment within the chamber 12.

The vacuum chamber 12 comprises a substrate support 22 defining a pathof substrate travel 24 extending substantially horizontally through thechamber 12. Preferably, the substrate support 22 is configured forsupporting a substrate 26 in a horizontal configuration (e.g., wherein atop major surface 28 of the substrate 26 is upwardly oriented while abottom major surface 30 of the substrate 26 is downwardly oriented)while the substrate 26 is being coated. In the embodiments shown inFIGS. 1-7 , the substrate support 22 comprises a plurality ofspaced-apart transport rollers that rotate to convey the substrate 26along the path of substrate travel 24. While the illustrated substratesupport 22 comprises a plurality of spaced-apart rollers, it is to beappreciated that other types of substrate supports can be used.

Substrates of various sizes can be used in the present invention.Commonly, large-area substrates are used. Certain embodiments involve asubstrate having a length and/or width of at least 0.5 meter, preferablyat least 1 meter, perhaps more preferably at least 1.5 meters (e.g.,between 2 meters and 4 meters), and in some cases at least 3 meters. Insome embodiments, the substrate is a jumbo glass sheet having a lengthand/or width that is between 3 meters and 10 meters, e.g., a glass sheethaving a width of 3.5 meters and a length of 6.5 meters. Substrateshaving a length and/or width of greater than 10 meters are alsoanticipated.

In some embodiments, the substrate is a square or rectangular glasssheet. The substrate in these embodiments can have any of the dimensionsdescribed in the preceding paragraph and/or the following paragraph. Inone embodiment, the substrate is a rectangular glass sheet having awidth of between 3 meters and 5 meters, such as about 3.5 meters, and alength of between 6 meters and 10 meters, such as about 6.5 meters.

Substrates of various thicknesses can be used in the present invention.In some embodiments, the substrate (which can optionally be a glasssheet) has a thickness of 1-8 mm. Certain embodiments involve asubstrate with a thickness of between 2.3 mm and 4.8 mm, and perhapsmore preferably between 2.5 mm and 4.8 mm. In one particular embodiment,a sheet of glass (e.g., soda-lime glass) with a thickness of 3 mm isused.

In certain embodiments, such as those illustrated in FIGS. 1-7 , thevacuum chamber 12 comprises a downward coating configuration adapted forcoating a top major surface 28 of the substrate 26. In such embodiments,the downward sputtering configuration comprises at least one cathodeassembly 14 positioned above the path of substrate travel 24.Additionally, the vacuum chamber 12 includes a gas distribution system18 positioned above the path of substrate travel 24.

In other embodiments (not shown), the vacuum chamber 12 can include anupward coating configuration adapted for coating a bottom major surface30 of the substrate 26. In such embodiments, the upward sputteringconfiguration comprises at least one lower cathode assembly 14positioned beneath the path of substrate travel 24. Here, the vacuumchamber 12 includes a lower gas distribution system 18 positionedbeneath the path of substrate travel 24. Upward sputtering systems aredescribed in U.S. patent application Ser. Nos. 09/868,542, 09/868,543,09/979,314, 09/572,766, and 09/599,301.

The cathode assembly 14 generally comprises a cylindrical target 16, amotor 32 and a magnet assembly 34. Generally, the cylindrical target 16includes a tubular backing formed of electrically conductive material,such as stainless steel, aluminum or any other suitably conductivematerial. The outer surface of the cylindrical target 16 is normallycoated with a sputterable target material, which is intended to besputtered onto the substrate surface 28.

Sputterable target material includes, but is not limited to, materialsuch as silicon, zinc, tin, silver, gold, chromium, aluminum, copper,nickel, titanium, niobium or combinations thereof. Compounds of variousmetals, such as nickel-chromium, can be sputtered using targets made ofthe desired compound. Silicon can also be used as cylindrical targetmaterial, for example, by plasma spraying silicon onto a support tube.In some embodiments, the sputterable target material comprises, consistsessentially of, or consists of a metallic material. In certainembodiments, the sputterable target material comprises, consistsessentially of, or consists of silver.

The cathode assembly 14 also includes a motor 32 operably connected tothe cylindrical target 16 by any clamping or bracketing means (notshown) known in the art. The clamping or bracketing device may be anytype of clamp, bracket, frame, fastener or support that keeps thecylindrical target 16 in a stationary position and does not affect therotation of the cylindrical target 16. The motor 32 can be any motorknown in the art (e.g., stepper motor, electric motor, hydraulic motorand/or pneumatic motor) that causes the cylindrical target 16 to rotateabout its longitudinal axis. Although a cylindrical target 16 isillustrated in the figures, skilled artisans would understand that aplanar target can instead be used.

The cathode assembly 14 further includes a magnet assembly 34. Themagnet assembly 34 includes any magnet assembly known in the art thatgenerates a plasma confinement field adjacent a surface of the target sothat a sputtering zone forms on a target surface. In some cases, themagnet assembly 34 is positioned within the target 16. In other cases,the magnet assembly 34 is positioned outside the target 16. Thesputtering zone can have any desired shape and in many embodiments is aracetrack-shaped sputtering zone.

The magnetron sputtering system 10 includes a new gas distributionsystem 18 that helps provide a generally uniform sputtering rate alongan entire sputtering zone. FIG. 7 illustrates a cylindrical target 16having a general sputtering zone 38 on a target surface 36. Thesputtering zone 38 generally has a first area 40, a second area 42 and athird area 44. The second area 42 is sandwiched between the first area40 and the third area 44. The sputtering zone 38 also extends for alongitudinal distance along a longitudinal axis LA of a cylindricaltarget. The first area 40 extends longitudinally along a longitudinaldistance 48, the second area 42 extends longitudinally along alongitudinal distance 50 and the third area 44 extends longitudinallyalong a longitudinal distance 52. The longitudinal distances 48, 50, 52do not overlap. Likewise, the areas 40, 42, 44 do not overlap.

The first area 40 has a first sputtering rate, the second area 42 has asecond sputtering rate and the third area 44 has a third sputtering ratewhen sputtered in an argon atmosphere. In some cases, the firstsputtering rate is higher than the second sputtering rate. In othercases, each the first and third sputtering rate is higher than thesecond sputtering rate. The new gas distribution system helps to providea more uniform sputtering rate along each of the areas 40, 42, 44.

In some embodiments, the gas distribution system 18 helps provide a moreuniform sputtering rate along a racetrack-shaped sputtering zone 38.FIG. 8 illustrates a cylindrical target 16 having a racetrack-shapedsputtering zone 38 on a target surface 36. While a racetrack-shapedsputtering zone is illustrated in many embodiments, skilled artisanswill understand that the sputtering zone can have any desired shape. Theplasma confinement field generally forms a race-track shaped electrondrift path on a target surface 36 which in turn forms theracetrack-shaped sputtering zone 38. The target surface 36 is generallythe surface that faces the substrate 26. For example, in cases where thetarget 16 is an upper target, the target surface 36 is a bottom surfacethat faces a substrate beneath. In cases where the target 16 is a lowertarget, the target surface 36 is an upper surface that faces a substrateabove. The cylindrical target 30 rotates during sputtering so that itsouter circumference of sputterable target material rotates through theracetrack-shaped sputtering zone 38.

The racetrack-shaped sputtering zone 38 generally includes twoturnaround areas 40, 44 and two straightaway areas 42, 46. Inparticular, the racetrack-shaped sputtering zone 38 includes a firstturnaround area 40, a first straightaway area 42, a second turnaroundarea 44 and a second straightaway area 46. Also, the first straightawayarea 42 (or the second straightaway area 46) is sandwiched between thefirst turnaround area 40 and the second turnaround area 44. Theracetrack-shaped sputtering zone 38 also extends for a longitudinaldistance along a longitudinal axis LA of a cylindrical target. Theracetrack-shaped sputtering zone 38 includes a first turnaround area 40that extends longitudinally along a longitudinal distance 48, a firststraightaway area 42 that extends longitudinally along a longitudinaldistance 50, a second turnaround area 44 that extends longitudinallyalong a longitudinal distance 52 and a second straightaway area 46 thatextends longitudinally along a longitudinal distance 50. In some cases,the two turnaround areas 40, 44 have a first sputtering rate and the twostraightaway areas 42, 46 have a second sputtering rate when sputteredin an argon atmosphere wherein the first sputtering rate is higher thanthe second sputtering rate. The new gas distribution system 18 helps toeven out the sputtering rates between the two turnaround areas 40, 44and the two straightaway areas 42, 26.

In certain embodiments, the gas distribution system 18 provides newarrangements of interfaces that each supply a particular gas mixture toa localized area on the sputtering zone. The gas mixture is selected tocontrol the sputtering rate along that localized area. Generally, thegas distribution system 18 includes at least a first interface and asecond interface. The first interface is positioned to supply gas to afirst localized area whereas the second interface is positioned tosupply gas to a second localized area. A first gas mixture is suppliedto the first interface and a second gas mixture is supplied to thesecond interface. The first gas mixture and the second gas mixture areselected such that the sputtering rate along the two localized areas aremore uniform.

In some embodiments, the first gas mixture includes inert gas “y” havinga first atomic weight and the second gas mixture includes inert gas “x”having a second atomic weight, wherein the first atomic weight isdifferent from the second atomic weight. In some cases, the secondatomic weight is heavier than the first atomic weight. A gas mixturewith a heavier atomic weight is supplied to a localized area where it isdesired to increase the sputtering rate relative to another localizedarea. Likewise, a gas mixture with a lighter atomic weight is suppliedto a localized area where it is desired to decrease the sputtering raterelative to another localized area. Argon is a standard sputtering gasand has an atomic weight of 39.95. Helium is a lighter gas than argonand has an atomic weight of 4.003. Krypton is a heavier gas than argonand has an atomic weight of 83.80.

In certain embodiments, the plurality of interfaces 62 includes at leasta first interface, a second interface and a third interface. In somecases, the third interface is sandwiched between the first interface andthe second interface. A first gas mixture is supplied to the firstinterface, a second gas mixture is supplied to the second interface anda third gas mixture is supplied to the third interface. Again, the threegas mixtures are selected such that the sputtering rates along the threelocalized areas are more uniform. Some embodiments above describe afirst interface and a second interface or a first interface, a secondinterface and a third interface. Each the first interface, the secondinterface and the third interface in these embodiments can comprise asingle interface or a plurality of interfaces or a set of interfaces.

In some embodiments, the first gas mixture includes inert gas “y” havinga first atomic weight, the second gas mixture includes inert gas “x”having a second atomic weight, and the third gas mixture includes inertgas “z” having a third atomic weight. In some cases, each the firstatomic weight, the second atomic weight and the third atomic weight aredifferent. In certain cases, the second atomic weight is heavier thanthe first atomic weight and the third atomic weight is heavier than thefirst atomic weight but is lighter than the second atomic weight.

In some cases, the plurality of interfaces are arranged to supply gas toa racetrack-shaped sputtering zone on the target. Referring back to theracetrack-shaped sputtering zone 38 of FIG. 8, the racetrack-shapedsputtering zone 38 extends for a longitudinal distance along alongitudinal axis LA of a cylindrical target and includes a firstturnaround area 40, a first straightaway area 42, a second turnaroundarea 44 and a second straightaway area 46.

In some cases, the gas distribution system 18 has a first interfacepositioned along either the first turnaround area 40 or the secondturnaround area 44 and a second interface positioned along either thefirst straightaway area 42 or the second straightaway area 46.Traditionally, the turnaround areas 40, 44 have a faster sputtering ratein an argon atmosphere than the straightaway areas 42, 46. In order tomake the sputtering rate across all these areas more uniform, the firstinterface can supply a gas mixture including an inert gas “y” having alighter atomic weight and the second interface can supply a gas mixtureincluding an inert gas “x” with a heavier atomic weight. When the gasmixture supplied to a turnaround area 40, 44 has lighter atomic weightthat the gas mixture supplied to the straightaway areas 42, 46, thesputtering rate becomes more uniform across each of these areas.

In other cases, the gas distribution system 18 has a first interfacepositioned along either the first turnaround area 40 or the secondturnaround area 44, a second interface positioned along either the firststraightaway area 42 or the second straightaway area 46 and a thirdinterface that is sandwiched between the first interface and the secondinterface. In this embodiment, the third interface can serve as anintermediate or transitional interface that supplies a gas mixtureincluding an inert gas “z” having a third atomic weight that is heavierthan the first atomic weight but lighter than the second atomic weight.

In some embodiments, the first gas mixture includes a single inert gasselected from the group consisting of argon, helium neon, krypton, xenonand radon and the first atomic weight is an atomic weight of the singleinert gas and/or the second gas mixture includes a single inert gasselected from the group consisting of argon, helium neon, krypton, xenonand radon and the second atomic weight is an atomic weight of the singleinert gas and/or the third gas mixture includes a single inert gasselected from the group consisting of argon, helium neon, krypton, xenonand radon and the third atomic weight is an atomic weight of the singleinert gas

In other embodiments, the first gas mixture includes an inert gasmixture including two or more inert gases selected from the groupconsisting of argon, helium neon, krypton, xenon and radon and the firstatomic weight is an average atomic weight of the two or more inert gasesand/or the second gas mixture includes an inert gas mixture includingtwo or more inert gases selected from the group consisting of argon,helium neon, krypton, xenon and radon and the second atomic weight is anaverage atomic weight of the two or more inert gases and/or the thirdgas mixture includes an inert gas mixture including two or more inertgases selected from the group consisting of argon, helium neon, krypton,xenon and radon and the third atomic weight is an average atomic weightof the two or more inert gases. In some cases, the first gas mixtureincludes a reactive gas in addition to the inert gas and/or the secondgas mixture includes a reactive gas in addition to the inert gas and/orthe third gas mixture includes a reactive gas in addition to the inertgas.

FIGS. 9-20 illustrate schematics of exemplary gas distribution systems18 having a plurality of interfaces 62 with different arrangements.These schematics are not to scale and are intended to illustrate generalconcepts. The embodiments of FIGS. 9-11 and 15-17 contemplate the use ofa single gas source 60. The single gas source 60 houses separate gassources that supply different gas mixtures. The embodiments of FIGS.12-14 and 18-20 contemplate the use of a first gas source 60 a and asecond gas source 60 b. Here, each of the gas sources 60 a, 60 b housesseparate gas sources that supply different gas mixtures. These differentembodiments are intended to show that any number of gas sources orarrangement of gas sources can be used to supply the gas mixtures “y,”“x,” and optically “z” to the interfaces 62 using any desired pipesystem known in the art.

The embodiments of FIGS. 9-14 include gas distribution systems 18 thathave at least a first interface and at least a second interface, whereinthe first interface is supplied with first gas mixture including aninert gas “y” and the second interface is supplied with a second gasmixture including an inert gas “x.” In some cases, both the first gasmixture and the second gas mixture are supplied at the same orsubstantially the same pressure. Likewise, in some embodiments, both thefirst gas mixture and the second gas mixture are free of orsubstantially free of a reactive gas.

The embodiments of FIGS. 15-20 include gas distribution systems 18 thathave at least a first interface, at least a second interface and atleast a third interface, wherein the first interface is supplied withfirst gas mixture including an inert gas “y,” the second interface issupplied with a second gas mixture including an inert gas “x” and thethird interface is supplied with a third gas mixture including an inertgas “z.” In some cases, the first gas mixture, the second gas mixtureand the third gas mixture are supplied at the same or substantially thesame pressure. Likewise, in some embodiments, the first gas mixture, thesecond gas mixture and the third gas mixture are free of orsubstantially free of a reactive gas.

Each of the interface arrangements shown in FIGS. 9-20 will now bedescribed in more detail. FIGS. 9 and 12 illustrates a gas distributionsystem 18 that includes a plurality of interfaces 62 that extend along alongitudinal axis LA of a target having a racetrack-shaped sputteringzone. The plurality of interfaces 62 are arranged along each side of thesputtering target. Each side includes first interfaces 62 a and secondinterfaces 62 b. In particular, on each side, the first interfaces 62 aare provided as outermost interfaces that sandwich a plurality of secondinterfaces 62 b. The interfaces first 62 a are positioned to supply afirst gas mixture including an inert gas “y” to the turnaround areas 40,44 of the racetrack-shaped sputtering zone. The second interfaces 62 bare positioned supply a second gas mixture including an inert gas “x” tothe straightaway areas 42, 46 of the racetrack-shaped sputtering zone.For example, the first interfaces 62 a can be positioned adjacent thefirst turnaround area 40 along a longitudinal distance 48 and/oradjacent the second turnaround area 44 along a longitudinal distance 52.Also, the second interfaces 62 a can be positioned adjacent the firststraightaway area 42 and/or the second straightaway area 46 along alongitudinal distance 50.

FIGS. 10 and 13 illustrates a gas distribution system 18 that includes aplurality of interfaces 62 that extend along a longitudinal axis LA of atarget having a racetrack-shaped sputtering zone. The plurality ofinterfaces 62 are arranged to substantially entirely surround thetarget. In fact, in some cases, the plurality of interfaces 62 are alsoarranged as a racetrack shape that substantially entirely surrounds theracetrack-shaped sputtering zone 38. Again, the first interfaces 62 aare positioned to supply a first gas mixture including an inert gas “y”to the turnaround areas 40, 44 of the racetrack-shaped sputtering zoneand the second interfaces 62 b are positioned supply a second gasmixture including an inert gas “x” to the straightaway areas 42, 46 ofthe racetrack-shaped sputtering zone. Here too, the first interfaces 62a can be positioned adjacent to (e.g., by substantially surrounding) thefirst turnaround area 40 along a longitudinal distance 48 and/oradjacent to (e.g., by substantially surrounding) the second turnaroundarea 44 along a longitudinal distance 52. Also, the second interfaces 62b can be positioned adjacent the first straightaway area 42 and/or thesecond straightaway area 46 along a longitudinal distance 50.

FIGS. 11 and 14 illustrates a gas distribution system 18 that includes aplurality of interfaces 62 that extend along a longitudinal axis LA of atarget having a racetrack-shaped sputtering zone. The plurality ofinterfaces 62 are arranged along each side of the sputtering target.Each side of interfaces 62 also partially surrounds ends of the target.Again, the first interfaces 62 a are positioned to supply a first gasmixture including an inert gas “y” to the turnaround areas 40, 44 of theracetrack-shaped sputtering zone and the second interfaces 62 b arepositioned supply a second gas mixture including an inert gas “x” to thestraightaway areas 42, 46 of the racetrack-shaped sputtering zone. Also,the first interfaces 62 a can be positioned adjacent to (e.g., bypartially surrounding) the first turnaround area 40 along a longitudinaldistance 68 and/or adjacent to (e.g., by partially surrounding) thesecond turnaround area 44 along a longitudinal distance 52. Also, thesecond interfaces 62 b can be positioned adjacent the first straightawayarea 42 and/or the second straightaway area 46 along a longitudinaldistance 50.

FIGS. 15 and 18 illustrates a gas distribution system 18 that includes aplurality of interfaces 62 that extend along a longitudinal axis LA of atarget having a racetrack-shaped sputtering zone. The plurality ofinterfaces 62 are arranged along each side of the sputtering target.Each side includes first interfaces 62 a, second interfaces 62 b andthird interfaces 62 c. Each third interface 62 is sandwiched between afirst interface 62 a and a plurality of second interfaces 62 b and thusserves as an intermediate or transitional interface. In particular, oneach side, first interfaces 62 a are provided as outermost interfacesthat sandwich an intermediate interface 62 c and a plurality of secondinterfaces 62 b. The first interfaces 62 a are positioned to supply afirst gas mixture including an inert gas “y” to the turnaround areas 40,44 of the racetrack-shaped sputtering zone. The second interfaces 62 bare positioned supply a second gas mixture including an inert gas “x” tothe straightaway areas 42, 46 of the racetrack-shaped sputtering zone.The third interfaces 62 c are positioned to supply a third gas mixtureincluding an inert gas “z” to the turnaround areas 40, 44 but aresandwiched in between the first interfaces 62 a and the secondinterfaces 62 b. For example, both the first interfaces 62 a and thethird interfaces 62 c can be positioned adjacent the first turnaroundarea 40 along a longitudinal distance 48 and/or adjacent the secondturnaround area 44 along a longitudinal distance 52. Also, the secondinterfaces 62 b can be positioned adjacent the first straightaway area42 and/or the second straightaway area 46 along a longitudinal distance50.

FIGS. 16 and 19 illustrates a gas distribution system 18 that includes aplurality of interfaces 62 that extend along a longitudinal axis LA of atarget having a racetrack-shaped sputtering zone. The plurality ofinterfaces 62 are arranged to substantially entirely surround thetarget. In fact, in some cases, the plurality of interfaces 62 are alsoarranged as a racetrack shape that substantially entirely surrounds theracetrack-shaped sputtering zone 38. The interfaces 62 include firstinterface 62 as, second interfaces 62 b and third interfaces 62 c. Eachthird interface 62 is sandwiched between a first interface 62 a and aplurality of second interfaces 62 b and thus serves as an intermediateor transitional interface. The first interfaces 62 a are positioned tosupply a first gas mixture including an inert gas “y” to the turnaroundareas 40, 44 of the racetrack-shaped sputtering zone. The secondinterfaces 62 b are positioned supply a second gas mixture including aninert gas “x” to the straightaway areas 42, 46 of the racetrack-shapedsputtering zone. The third interfaces 62 c are positioned to supply athird gas mixture including an inert gas “z” to the turnaround areas 40,44 but are sandwiched in between the first interfaces 62 a and thesecond interfaces 62 b. The first interfaces 62 a and the secondinterfaces 62 c can be positioned adjacent to (e.g., by substantiallysurrounding) the first turnaround area 40 along a longitudinal distance48 and/or adjacent to (e.g., by substantially surrounding) the secondturnaround area 44 along a longitudinal distance 52. Also, the secondinterfaces 62 b can be positioned adjacent the first straightaway area42 and/or the second straightaway area 46 along a longitudinal distance50.

FIGS. 17 and 20 illustrates a gas distribution system 18 that includes aplurality of interfaces 62 that extend along a longitudinal axis LA of atarget having a racetrack-shaped sputtering zone. The plurality ofinterfaces 62 are arranged along each side of the sputtering target.Each side of interfaces 62 also partially surrounds ends of the target.Again, the first interfaces 62 a are positioned to supply a first gasmixture including an inert gas “y” to the turnaround areas 40, 44 of theracetrack-shaped sputtering zone. The second interfaces 62 b arepositioned supply a second gas mixture including an inert gas “x” to thestraightaway areas 42, 46 of the racetrack-shaped sputtering zone. Thethird interfaces 62 c are positioned to supply a third gas mixtureincluding an inert gas “z” to the turnaround areas 40, 44 but aresandwiched in between the first interfaces 62 a and the secondinterfaces 62 b. Also, the first interfaces 62 a and third interfaces 62c can be positioned adjacent to (e.g., by partially surrounding) thefirst turnaround area 40 along a longitudinal distance 68 and/oradjacent to (e.g., by partially surrounding) the second turnaround area44 along a longitudinal distance 52. Also, the second interfaces 62 bcan be positioned adjacent the first straightaway area 42 and/or thesecond straightaway area 46 along a longitudinal distance 50.

In each of the embodiments of FIGS. 9-20 , in some cases, the first gasmixture “y” includes a single inert gas selected from the groupconsisting of argon, helium neon, krypton, xenon and radon and the firstatomic weight is an atomic weight of the single inert gas and/or thesecond gas mixture “x” includes a single inert gas selected from thegroup consisting of argon, helium neon, krypton, xenon and radon and thesecond atomic weight is an atomic weight of the single inert gas and/orthe third gas mixture “z” includes a single inert gas selected from thegroup consisting of argon, helium neon, krypton, xenon and radon and thethird atomic weight is an atomic weight of the single inert gas. Inother cases, the first gas mixture “y” includes an inert gas mixtureincluding two or more inert gases selected from the group consisting ofargon, helium neon, krypton, xenon and radon and the first atomic weightis an average atomic weight of the two or more inert gases and/or thesecond gas mixture “x” includes an inert gas mixture including two ormore inert gases selected from the group consisting of argon, heliumneon, krypton, xenon and radon and the second atomic weight is anaverage atomic weight of the two or more inert gases and/or the thirdgas mixture “z” includes an inert gas mixture including two or moreinert gases selected from the group consisting of argon, helium neon,krypton, xenon and radon and the third atomic weight is an averageatomic weight of the two or more inert gases. In some cases, the firstgas mixture “y” includes a reactive gas in addition to the inert gasand/or the second gas mixture “x” includes a reactive gas in addition tothe inert gas and/or the third gas mixture “y” includes a reactive gasin addition to the inert gas.

In some embodiments, the gas distribution system 18 is used in anon-reactive sputtering process. In these embodiments, the gasdistribution system 18 does not introduce reactive gases such as oxygenor nitrogen into the sputtering chamber. Instead, the gas distributionsystem 18 only introduces inert gases. In other words, the gasdistribution system supplies gas that is free of or substantially freeof a reactive gas. The non-reactive sputtering process can be either anon-reactive sputtering process for depositing metallic film or anon-reactive sputtering process for depositing dielectric film.

In certain embodiments, each the first gas mixture “y,” the second gasmixture “x,” and the third gas mixture “y” is substantially free of areactive gas. For example, in some cases, the first gas mixture “y”consists essentially of or consists of a single inert gas selected fromthe group consisting of argon, helium neon, krypton, xenon and radon andthe first atomic weight is an atomic weight of the single inert gas. Thesecond gas mixture “x” consists essentially of or consists of a singleinert gas selected from the group consisting of argon, helium neon,krypton, xenon and radon and the second atomic weight is an atomicweight of the single inert gas. The third gas mixture “z” consistsessentially of or consists of a single inert gas selected from the groupconsisting of argon, helium neon, krypton, xenon and radon and the thirdatomic weight is an atomic weight of the single inert gas.

In other cases, the first gas mixture “y” consists essentially of orconsists of an inert gas mixture including two or more inert gasesselected from the group consisting of argon, helium neon, krypton, xenonand radon and the first atomic weight is an average atomic weight of thetwo or more inert gases. The second gas mixture “x” consists essentiallyof or consists of an inert gas mixture including two or more inert gasesselected from the group consisting of argon, helium neon, krypton, xenonand radon and the second atomic weight is an average atomic weight ofthe two or more inert gases. The third gas mixture “z” consistsessentially of or consists of an inert gas mixture including two or moreinert gases selected from the group consisting of argon, helium neon,krypton, xenon and radon and the third atomic weight is an averageatomic weight of the two or more inert gases.

In certain cases, the gas distribution system 18 is used with asputtering target that includes sputterable material having a sputteringrate that is not modified by surface chemistry of the sputterablematerial. In certain embodiments, the gas distribution system 18 is usedin a non-reactive sputtering process for depositing a metallic film suchas metallic silver or metallic titanium. In these embodiments, thesputterable material in the sputtering target consists essentially of orconsists of a metallic material such as metallic silver or metallictitanium. The gas distribution system 18 is used to sputter deposit amore uniform metallic film onto the substrate.

In some embodiments, the gas distribution system 18 includes a pluralityof interfaces 62 that each introduces gas at the same or substantiallythe same pressure. For example, the interface that supplies the firstgas mixture “y” will supply gas at the same or substantially the samepressure as the interface that supplies a second gas mixture “x.”

In other embodiments, the plurality of interfaces 62 can include one ormore interfaces that introduce gas continuously, for example at acontinuous flow rate and/or at a continuous pressure. In some cases, allof the interfaces introduce gas continuously at the same flow rate. Inother cases, certain of the interfaces introduce gas continuously at oneflow rate whereas other interfaces introduce gas at another flow rate.Also, in some cases, all of the interfaces introduce gas continuously atthe same pressure. In other cases, certain of the interfaces introducegas continuously at one pressure whereas other interfaces introduce gasat another pressure.

In other embodiments, the plurality of interfaces 62 can include one ormore interfaces that introduce gas non-continuously, for example bypulsing, such as by pulsing the flow rate or flow burst lengths and/orby pulsing the pressure. In some cases, all of the interfaces introducegas by pulsing the flow rate or the flow burst lengths. In other cases,certain of the interfaces introduce gas continuously at one flow ratewhereas other interfaces introduce gas by pulsing the flow rate or flowburst lengths. Also, in some cases, all of the interfaces introduce gasby pulsing the pressure. In other cases, certain of the interfacesintroduce gas continuously at one pressure whereas other interfacesintroduce gas by pulsing the pressure. Any desired combination ofpulsing or non-pulsing can be provided to different arrangement ofinterfaces to help to adjust the local sputtering rates to help promotesputtering uniformity.

The plurality of interfaces 62 shown in FIGS. 9-20 can be provided aspart of one or more gas delivery members. The gas delivery members canbe configured as any desired structure that delivers gas through aplurality of interfaces. For example, the plurality of interfaces can beprovided as part of the gas delivery member structure. Examples of gasdelivery members include, but are not limited to, tubes, shafts, ducts,bars and beams. Likewise, the interfaces can be formed as manifolds,nozzles, openings or other structures that supply gas. The gas deliverymembers can also have one or more internal partitions (not shown) toensure that different gas mixtures are separated and supplied to theappropriate interface.

In some embodiments, one or more gas delivery members are positionedalong each side of a sputtering target. For example, in FIGS. 1-2 and 21, a first gas delivery member 54 is positioned on one side of the target16 and a second gas delivery member 56 is positioned on an opposite sideof the target. The gas delivery members of 54, 56 can include interfacesarranged according to any of the embodiments already described, forexample the embodiments of FIG. 9, 12, 15 or 18 . In FIGS. 3-4 and 22 ,a single gas delivery member 55 is provided and is positioned tosubstantially entirely surround the target 16. The single gas deliverymember can include interfaces arranged according to any of theembodiments already described, for example the embodiments of FIG. 10,13, 16 or 19 . In FIGS. 5-6 and 23 , a first gas delivery member 54 ispositioned on one side of the target 16 and a second gas delivery member56 is positioned on an opposite side of the target, wherein both gasdelivery members 54, 56 also partially surround ends of the target. Thegas delivery members of 54, 56 can include interfaces arranged accordingto any of the embodiments already described, for example the embodimentsof FIG. 11, 14, 17 or 20 .

Other embodiments of the invention provide a gas distribution system 18having certain gas delivery members that are anodic. In such cases, thegas distribution system 18 includes a plurality gas distributionmembers, wherein the plurality of gas distribution members includes aplurality of anodic gas distribution members. Each anodic gasdistribution member can be provided using principles and embodimentsdiscussed in Applicant's own U.S. Pat. No. 7,166,199, the entirecontents of which are herein incorporated by reference.

Each anodic gas distribution member is insulated from the other gasdistribution members and from the grounded sputtering chamber. Applicanthas discovered that by using a plurality of anodic gas distributionmembers, different voltages can be applied to different anodic gasdistribution members to help control local sputtering rates. Forexample, when a higher voltage is supplied to an anodic gas distributionmember, the higher voltage will collect more electrons from the localplasma to reduce the local sputtering rate.

In some cases, the gas distribution system 18 includes one or moreanodic gas distribution members arrange so as to reduce the localsputtering rate at turnaround areas 40, 44 of a racetrack-shapedsputtering zone. As such, in some cases, the gas distribution system 18includes at least one anodic gas distribution member, wherein the anodicgas distribution member is insulated from other gas distribution membersand the sputtering chamber. The anodic gas distribution member suppliesgas to either the first turnaround area 40 or the second turnaround area44 and receives a voltage that reduces a local sputtering rate ascompared to other gas distribution systems that are not anodic or thatare anodic but receive a lower voltage.

A first anodic gas distribution member and a second anodic gasdistribution member, wherein the first anodic gas distribution member isinsulated from the second anodic gas distribution member, and whereinthe first anodic gas distribution remember receives a first voltage andthe second anodic gas distribution member receives a second voltage,wherein the first voltage is different than the second voltage.

FIG. 24 illustrates one embodiment of a gas distribution systemincluding anodic gas distribution members. A plurality of gasdistribution members 54 a, 54 b and 54 c are arranged along one side ofa sputtering target and a plurality of gas distribution members 56 a, 56b and 56 c are arranged along an opposite side of the sputtering target.In some embodiments, gas distribution members 54 a, 56 a, 54 c, 56 c areanodic whereas gas distribution members 54 b, 56 b are not anodic. Theanodic members 54 a, 56 a, 54 c, 56 c supply gas to turnaround areas 40,44 of a racetrack-shaped sputtering zone. Preferably, the anodic members54 a, 56 a, 54 c, 56 c are provided with a voltage that reduces thesputtering rate along the turnaround areas 40, 44 relative to thesputtering rate along the straightaway areas 42, 46.

In another embodiment, also shown in FIG. 24 , all of the gasdistribution members 54 a, 54 b, 54 c, 56 a, 56 b, 56 c are anodic.Here, the gas distribution members 54 a, 56 a, 54 c, 56 c receive afirst voltage whereas gas distribution members 54 b, 56 b receive asecond voltage, wherein the first voltage and the second voltage aredifferent. In many cases, it is desirable to reduce the sputtering rateat the turnaround areas 40, 44 relative to the straightaway areas 42,46, so the first voltage is higher than the second voltage.

In some cases, the gas delivery members shown in FIG. 24 can include theplurality of interfaces arrangement shown in either FIG. 9 or 12 . Insuch cases, the gas delivery members 54 a, 54 c, 56 a, 56 c can includefirst interfaces 62 a that supply a first gas mixture including an inertgas “y” and the gas delivery members 54 b, 56 c can include secondinterfaces 62 b that supply a second gas mixture including an inert gas“x.”

FIG. 25 illustrates another embodiment of a gas distribution systemincluding anodic gas distribution members. A plurality of gasdistribution members 55 a, 55 b, 55 c, 55 d are arranged tosubstantially entirely surround a sputtering target. In someembodiments, gas distribution members 55 b, 55 d are anodic whereas gasdistribution members 55 a, 55 c are not anodic. The anodic members 55 b,55 d supply gas to turnaround areas 40, 44 of a racetrack-shapedsputtering zone whereas non-anodic members 55 a, 55 c supply gas tostraightaway areas 42, 46. Preferably, the anodic members 55 b, 55 d areprovided with a voltage that reduces the sputtering rate along theturnaround areas 40, 44 relative to the sputtering rate along thestraightaway areas 42, 46.

In another embodiment, also shown in FIG. 25 , all of the gasdistribution members 55 a, 55 b, 55 c, 55 d are anodic. Here, the gasdistribution members 55 b, 55 d receive a first voltage whereas gasdistribution members 55 a, 55 c receive a second voltage, wherein thefirst voltage and the second voltage are different. In many cases, it isdesirable to reduce the sputtering rate at the turnaround areas 40, 44relative to the straightaway areas 42, 46, so the first voltage ishigher than the second voltage.

Also, in some cases, the gas delivery members shown in FIG. 25 caninclude the plurality of interfaces arrangement shown in either FIG. 10or 13 . In such cases, the gas delivery members 55 b, 55 d can includefirst interfaces 62 a that supply a first gas mixture including an inertgas “y” and the gas delivery members 55 a, 55 c can include secondinterfaces 62 b that supply a second gas mixture including an inert gas“x.”

FIG. 26 illustrates another embodiment of a gas distribution systemincluding anodic gas distribution members. A plurality of gasdistribution members 55 a, 55 b, 55 c, 55 d, 55 d, 55 e, 55 f, 55 g, 55h are arranged to substantially entirely surround a sputtering target.In some embodiments, gas distribution members 55 b, 55 c, 55 d, 55 e, 55f, 55 g, 55 h are anodic whereas gas distribution members 55 a, 55 e arenot anodic. The anodic members 55 b, 55 c, 55 d, 55 e, 55 f, 55 g, 55 hsupply gas to turnaround areas 40, 44 of a racetrack-shaped sputteringzone whereas non-anodic members 55 a, 55 e supply gas to straightawayareas 42, 46. Preferably, the anodic members 55 b, 55 c, 55 d, 55 e, 55f, 55 g, 55 h are provided with a voltage that reduces the sputteringrate along the turnaround areas 40, 44 relative to the sputtering ratealong the straightaway areas 42, 46. In particular embodiments, anodicmembers 55 b, 55 d, 55 f, 55 h receive a first voltage and anodicmembers 55 c, 55 g receive a second voltage. For example, the anodicmembers 55 c, 55 g can serve as transitional or intermediate anodicmembers that have a lower voltage than anodic members 55 b, 55 d, 55 f,55 h. Thus, in some cases, the first voltage is higher than the secondvoltage.

In another embodiment, also shown in FIG. 26 , all of the gasdistribution members 55 a, 55 b, 55 c, 55 d, 55 d, 55 e, 55 f, 55 g, 55h are anodic. Here, the gas distribution members 55 c, 55 g receive afirst voltage, gas distribution members 55 b, 55 e, 55 f, 55 h receive asecond voltage and gas distribution members 55 a, 55 e receive a thirdvoltage, wherein the first voltage, the second voltage and the thirdvoltage are different. In many cases, the first voltage is higher thanthe second voltage and the second voltage is higher than the thirdvoltage.

Also, in some cases, the gas delivery members shown in FIG. 26 caninclude the plurality of interfaces arrangement shown in either FIG. 16or 19 . In such cases, the gas delivery members 55 c, 55 g can includefirst interfaces 62 a that supply a first gas mixture including an inertgas “y,” the gas delivery members 55 b, 55 e, 55 f, 55 h can includethird interfaces 62 c that supply a third gas mixture including an inertgas “z” and the gas delivery members 55 a, 55 e include the secondinterfaces 62 b that supply the second gas mixture “x.”

FIG. 27 illustrates another embodiment of a gas distribution systemincluding anodic gas distribution members. A plurality of gasdistribution members 54 a, 54 b and 54 c are arranged along one side ofa sputtering target and a plurality of gas distribution members 56 a, 56b and 56 c are arranged along an opposite side of the sputtering target.Also, gas distribution members 54 a, 54 c, 56 a, 56 c are arranged topartially surround ends of the sputtering target. In some embodiments,gas distribution members 54 a, 56 a, 54 c, 56 c are anodic whereas gasdistribution members 54 b, 56 b are not anodic. The anodic members 54 a,56 a, 54 c, 56 c supply gas to turnaround areas 40, 44 of aracetrack-shaped sputtering zone. Preferably, the anodic members 54 a,56 a, 54 c, 56 c are provided with a voltage that reduces the sputteringrate along the turnaround areas 40, 44 relative to the sputtering ratealong the straightaway areas 42, 46.

In another embodiment, also shown in FIG. 27 , all of the gasdistribution members 54 a, 54 b, 54 c, 56 a, 56 b, 56 c are anodic.Here, the gas distribution members 54 a, 56 a, 54 c, 56 c receive afirst voltage whereas gas distribution members 54 b, 56 b receive asecond voltage, wherein the first voltage and the second voltage aredifferent. In many cases, it is desirable to reduce the sputtering rateat the turnaround areas 40, 44 relative to the straightaway areas 42,46, so the first voltage is higher than the second voltage.

Also, in some cases, the gas delivery members shown in FIG. 27 caninclude the plurality of interfaces arrangement shown in either FIG. 11or 14 . In such cases, the gas delivery members 54 a, 56 a, 54 c, 56 ccan include first interfaces 62 a that supply a first gas mixtureincluding an inert gas “y” and the gas delivery members 54 b, 56 binclude the second interfaces 62 b that supply the second gas mixture“x.”

In each of the embodiments of FIGS. 24-27 , each of the anodic membersare insulated from other anodic members and non-anodic members. Eachanodic member can be provided with a voltage from a single voltagesource or a plurality of different voltage sources. Likewise, eachvoltage source(s) can be a set voltage or an adjustable voltage. Also,each of the anodic members can be provided with the same voltage or withdifferent voltages. Even further, each of the anodic members can beprovided with a continuous voltage or with a pulsed voltage. A pulsedvoltage can be pulsed in voltage intensity and/or in voltage frequency.Any desired combination of set or adjustable voltages or pulsing ornon-pulsing voltages can be provided to different arrangement ofinterfaces help to adjust the local sputtering rates to help promotesputtering uniformity.

Also, embodiments of the gas distribution system including one or moreanodic gas delivery members can be used in combination with any of theembodiments of the gas distribution system including a plurality ofinterface arrangements. Any combination of any of the embodimentsdisclosed is within the scope of the invention.

While some preferred embodiments of the invention have been described,it should be understood that various changes, adaptations andmodifications may be made therein without departing from the spirit ofthe invention and the scope of the appended claims.

What is claimed is:
 1. A method of using a magnetron sputteringapparatus that comprises a vacuum chamber having a controlledenvironment, the magnetron sputtering apparatus including a targetcomprising one or more sputterable materials, wherein the targetincludes a sputtering zone that is racetrack shaped and extendslongitudinally along a longitudinal axis, the sputtering zone includingtwo straightaway areas sandwiched between first and second turnaroundareas, the magnetron sputtering apparatus further including a gasdistribution system comprising a plurality of interfaces located alongthe longitudinal axis and arranged to entirely surround the target,wherein the plurality of interfaces comprises a plurality of firstinterfaces and a plurality of second interfaces, the first interfacespositioned to surround both of the first and second turnaround areas tosupply a first gas mixture to both of the first and second turnaroundareas, such that the first gas mixture controls sputtering rate atlocalized areas of both of the first and second turnaround areas,whereas the second interfaces are positioned at each of the twostraightaway areas to supply a second gas mixture to both of the twostraightaway areas, such that the second gas mixture controls sputteringrate at localized areas of both of the two straightaway areas, the firstinterfaces positioned along first and third longitudinal distances, thesecond interfaces positioned along a second longitudinal distance, suchthat the first, second, and third longitudinal distances do not overlap,the magnetron sputtering apparatus comprising a first gas source and asecond gas source, the first gas source and the second gas source eachhousing separate gas sources that supply different gas mixtures fromeach other, the method comprising: supplying the first gas mixture fromthe first gas source to the first interfaces, wherein the first gasmixture comprises a single inert gas “y” or two or more inert gasesincluding inert gas “y” having a first atomic weight, wherein the firstatomic weight is an atomic weight of the single inert gas “y” or anaverage atomic weight of the two or more inert gases in the first gasmixture; supplying the second gas mixture from the second gas source tothe second interfaces, wherein the second gas mixture comprises a singleinert gas “x” or two or more inert gases including inert gas “x” havinga second atomic weight, wherein the second atomic weight is an atomicweight of the single inert gas “x” or an average atomic weight of thetwo or more inert gases in the second gas mixture; wherein the inert gas“y” is different from the inert gas “x”, and wherein the first atomicweight is different from the second atomic weight, the second atomicweight being heavier than the first atomic weight, the gas distributionsystem thereby providing more uniform sputtering rates across the firstand second turnaround areas and the two straightaway areas than if onlyan argon gas atmosphere were provided to the first and second turnaroundareas and the two straightaway areas, the inert gas “x” being of heavieratomic weight than the inert gas “y”.
 2. The method of claim 1 whereinthe supplying the first gas mixture includes supplying a reactive gas inaddition to the single inert gas “y” or the two or more inert gasesincluding inert gas “y” having the first atomic weight, and/or thesupplying the second gas mixture includes supplying a reactive gas inaddition to the single inert gas “x” or the two or more inert gasesincluding inert gas “x” having the second atomic weight.
 3. The methodof claim 1 wherein the single inert gas “y” of the first gas mixture isselected from the group consisting of argon, helium, neon, krypton, andxenon and the first atomic weight is the atomic weight of the singleinert gas “y” of the first gas mixture, and/or the single inert gas “x”of the second gas mixture is selected from the group consisting ofargon, neon, krypton, xenon and radon and the second atomic weight isthe atomic weight of the single inert gas “x” of the second gas mixture.4. The method of claim 1 wherein at least one interface in the pluralityof interfaces supplies gas at a continuous flow rate and/or at acontinuous pressure.
 5. The method of claim 1 wherein the first gasmixture is supplied to the first interfaces at a first gas pressure andthe second gas mixture is supplied to the second interfaces at a secondgas pressure, wherein the first gas pressure is substantially the sameas the second gas pressure.
 6. The method of claim 1 wherein the gasdistribution system includes an anodic gas distribution member thathouses the first interfaces, and the method involves the anodic gasdistribution member receiving a voltage that reduces the sputtering rateof the first turnaround area or the second turnaround area relative tothe sputtering rate of the two straightaway areas.
 7. The method ofclaim 1 wherein the one or more sputterable materials of the targetcomprise silver.
 8. The method of claim 1 wherein the one or moresputterable materials of the target consist of silver.
 9. The method ofclaim 1 wherein the target is cylindrical.
 10. The method of claim 1wherein the plurality of interfaces are part of a gas delivery memberstructure comprising one or more gas delivery members each positionedalong a side of the target.
 11. The method of claim 1 wherein theplurality of interfaces further includes a third interface, the methodfurther comprising supplying a third gas mixture to the third interface,wherein the third gas mixture includes a single inert gas “z” or two ormore inert gases including inert gas “z” having a third atomic weight,wherein the third atomic weight is an atomic weight of the single inertgas “z” or an average atomic weight of two or more inert gases includinginert gas “z” of the third gas mixture, and wherein the third atomicweight is different from each of the first atomic weight and the secondatomic weight.
 12. The method of claim 11 wherein the second atomicweight is heavier than the first atomic weight and wherein the thirdatomic weight is heavier than the first atomic weight but is lighterthan the second atomic weight.
 13. The method of claim 11 wherein thefirst gas mixture is supplied to the first interfaces at a first gaspressure, the second gas mixture is supplied to the second interfaces ata second gas pressure, and the third gas mixture is supplied to thethird interface at a third gas pressure, wherein the first gas pressure,the second gas pressure, and the third gas pressure are substantiallythe same.
 14. The method of claim 1 wherein at least one interface inthe plurality of interfaces supplies gas at a non-continuous flow rateand/or at a non-continuous pressure.
 15. The method of claim 1 whereinthe vacuum chamber comprises a substrate support defining a path ofsubstrate travel, and the method comprises conveying a substrate alongthe path of substrate travel during operation of the magnetronsputtering apparatus, the substrate support comprising a plurality ofspaced-apart transport rollers that rotate to convey the substrate alongthe path of substrate travel during the operation of the magnetronsputtering apparatus.